Removable burner assembly



May 8, 1962 H. STlERLlN REMOVABLE BURNER ASSEMBLY Filed Nov. 17, 1958/NVENTDR l/A N5 Shin/Al A ATTORIVEY 3,033,272 REMOVABLE BURNER ASSEMBLYHans Stierlin, Rainweg 15, Schlieren, Zurich, Switzerland Filed Nov. 17,195$, Ser. No. 774,205 Claims priority, application Switzerland Nov. 18,1957 8 Claims. (1. 158-4) This invention relates to oil burning ovens orfurnaces of the open pot burner type and more particularly to theconstruction of the burner assembly thereof.

An object of the invention is to facilitate the servicing, repairing andcleaning of oil burners of the pot type by, facilitating access to theelements of the burner assembly.

A further object of the invention is to provide oil ovens of which theburner and its associated elements may be removed from the oven orfurnace per so without uncoupling threaded fittings or disconnectingwires of the electric system thereof.

Still another object is to construct the burner per se, the fuel tank,and the blower of an oil burning oven or furnace as a removable andinterchangeable unit in order to expedite restoration of the oven orfurnace being cleaned or requiring repairs, back into service. i

The oil burner of oil furnaces of the pot type must be removed from thefurnace or oven per se for inspection, adjustment, cleaning and repairthereof. Of necessity, the burner has an oil line to the fuel regulatorand the tank, which line must be disconnected when dismantling theburner of prior art furnaces. To permit ofsuch disconnection, the oilline is attached to the burner by means of threaded fittings which canbe loosened with tools or by means of large wing nuts. The burner itselfcan beremoved from the main body of the furnace or oven by looseningscrew fittings or opening bayonet or other type connectors. If theburner is provided with a fan, the electric connections thereto mustalso be removed.

in practice, the disconnection of so many lines and the necessity ofrestoring all of them has resulted in serious difiiculties, as alsodefects in the reassembled burner aggregate. Frequently such work isdone by personnel not fully acquainted with the particular burner. Thusit happens that, on reassembly of the burner, the oil line drips, or theelectrical connections are faultily or wholly incorrectly restored, sothat the burner cannot operate, or operates defectively, or thatfouling, dirtying, or even fires, result from oil drippings.Furthermore, prolonged work upon the always dirty burners makes fordirtying work by the serviceman. And if, in addition the burner controlsare automatic, dismantling and reassembly of the burner is socomplicated, that only specially trained personnel should undertake suchwork.

There are prior known oil furnaces of the pot type in which thevaporizer-burner is made pivotable for facility in lighting and cleaningit. The connection between the float valve control and the vaporizer isby a heat-resistant tube of synthetic material; but even in suchconstruction when the furnace is to be dismantled because repairs arerequired, the burner assembly must still be completely disassembled,including the disconnection of many, more or less diflicultlyaccessible, connecting points in the lines, pipes and cables. Withfurnaces of such construction, on the occurrence of a major fault, thefurnace is frequently out of operation for several hours, which, ofcourse, is not at all desirable.

Also prior known are non-automatically controlled oil furnaces of thepot type in which a pivotally disposed aggregate, consisting of thebottom member of the pot burner and the oil reservoir, as also of somerigid connections therebetween, may be lifted from the furnace. In suchconstruction, the oil tank is disposed externally of the furnace.Lifting the aggregate out of and reinserting it into the pivoted forkson which it is supported 3,033,272 Patented May 8, 1952 is, however,quite burdensome. In still another prior known type furnace, the burneraggregate is disposed telescopically in the furnace, the aggregateincluding the controls being connected to an external tank by a seven,able connection, which may cause oil dripping, as above explained. Theelectrical lines must alsobe disconnected from the supply line in thisconstruction before the aggregate can be withdrawn from the furnace.Furthermore, in such construction, which is simply pushed back into thefurnace, the sealing problem of the pot burner to the flame chamber isby no means satisfactorily solved,

The furnace construction according to the instant invention avoids allof the foregoing shortcomings and is an interchangeable unit consistingof the elements of the burner assembly which is characterized in thatthe entire unit, including a base which forms the oil tank, may beraised and lowered, the burner shell being resiliently supported on theoil tank so that the unit, after it has been lowered, may be pulled fromthe furnace.

Two illustrative embodiments of the invention will now be described andexplained in detail with the aid of the annexed drawing, in which: 7

FIGURE 1 shows the section of the first embodiment of the oil oven ofthe pot type of my invention, showing the burner assembly in operativecondition; and

FIGURE 2 shows the corresponding section of the second embodiment, butwith the burner group out of the operative condition.

In the fully automatic oil oven of FIGURE 1, the flame chamber 1 isprovided with a smoke stack or chimney (not shown) and with a body 3constituting a single structural unit within the oven having verticaland horizontal walls forming a hollow body. An oil tank 4 forms asupporting base for the entire interchangeable burner assembly, a potburner 6 being supported by springs 14; thereon, together with the otherelements required for automatic operation. Each of the springs 14 ishoused in an open-ended vertical cylinder 14A affixed to the top of tank4 and is braced against the lower end of piston 15 within such cylinder,the upper ends of the pistons sup-, porting the pot burner assembly.Upward movement of each of pistons 15 is limited by the engagement of anoutwardly extending annular shoulder at the lower end of the pistonengaging an internally extending flange 14B at the top end region of itsenveloping cylinder 14A. At the forward portion of tank 4, on aforwardly projecting tongue, a lever 10 having a long and a short armand vertically pivotable, is journalled therein, the short arm beingprovided with rollers 11 at its free end which ride on the bottomhorizontal wall of the oven body. The rear portion of the tank, whichinclines downwardly from front to rear, is also supported by rollers 11'on straps integral with the tank which rollers 11 likewise are inrolling contact with the bottom wall of the oven body. Rollers 11 and11, which may run on a track (not shown) on the bottom horizontal wallof the body, permit the burner assembly readily to be pulled fromwithin, and to be pushed back into, the interior of the oven body 3.Obviously, slides may be used instead of rollers. Nhen lever llii ismoved upwardly in the directionof the arrow (FIG. 2), the entire burnerassembly moves upwardly (FIG. 1), pivoting about the shaft of rearrollers 11' as the front rollers are brought from below the front bottomof the tank to forward of the tank by such movement of lever 10. In sodoing, the upper rim region of the cylindrical wall 6A of the pot burner6 is moved into a conical annular groove 12 of a cast ring forming thebottom of flame chamber 1. Pot burner 6 has a centrally dished bottom613 from the periphery of which the integral cylindrical wall 6A extendsupwardly, Wall 6A having a plurality of air inlet ports 6C. An open topcylindrical casing 61) having its upper end sealed to the upper regionof the cylindrical wall 6A very close to the upper rim thereof,surrounds cylindrical wall 6A. A blower fan is positioned below dishedbottom 63 of the burner. Springs 14 continuously and tightly press theupper rim region of pot burner 6 against the cast ring 13. The fuel feedelement is a scoop conveyor 16 driven by an electric motor 17 which maybe of the variable speed or synchronous types, the bucket or scoopconveyor and the pot burner 6 being connected to each other by oil lines18 and 19. Within the pot burner 6, and extending from the bottomthereof, there is disposed an electrical ignition device 22 connected byline 23 to a distributor 25, while fan or blower 26 is disposed belowthe pot burner. The fan is driven by a motor 27 connected by line 28 tothe distributor 25. The air blown by fan 26 through ports 6C of theburner cylindrical wall is thus mixed with the supplied oil in themixing chamber formed by the burner dished bottom and its integralcylindrical wall. The fuel oil standpipe 30 is provided with a drainvalve 31 having a bimetal strip 32 at the upper end of its valve rod forcontrol purposes thereof. Electrical connection of the oil furnace tothe line is by means of a plug 42 and a coupling 33, 33. The details ofthe oil burner per se and its fuel supply with the standpipe, drainvalve and bimetal strip, are described in detail in my copendingapplication for patent, Serial Number 697,219, filed November 18, 1957,for Pot Type Oil Burner, which description is herewith incorporated byreference. In the inserted position of the assembly, the tank rear wallis against a resilient stop 34 on the rear vertical wall of the ovenbody. A door 35 in the oven body front vertical wall serves the purposeof access to the assembly and to lever 10.

Interchange of the burner assembly is accomplished as follows: Uponopening door 35, access to lever is possible. The upper and handle endof lever 16 is pulled forward and then lowered, thus swiveling the frontrollers 11 to the rear causing the assembly to be lowered. In so doing,the upper rim of the cylindrical wall of the pot burner 6 moves out ofthe conical groove 12 of ring 13 and the coupling 33, 33' is opened.Thus the assembly can be completely withdrawn from the oven body and, ifrepairs are required, may be replaced by an operatingready replacementassembly. On reintroduction of a burner assembly into the oven body, theassembly is pushed back against stop 34 and lever 10 is restored to thevertical position as shown in FIGURE 1 and the oven is restored tooperativeness, the upper rim of the cylindrical wall of the burner beingcontinuously pressed against ring 13 by support springs 14. If theactuation of lever 19 back to its vertical position should be forgotten,the oven door 35 cannot be reclosed, calling attention to the oversight.When the oil tank 4 requires refilling, the burner assembly is pulledout, cover 4:; of the front portion of the tank is removed and the tankrefilled, the cover replaced, and the tank is pushed back into the ovenbody. Then the mixing chamber is sealed to the flame chamber byrestoring the lever to its vertical position, the oven door beingthereupon closed.

In the embodiment shown in FIGURE 2, the room oven is connected by afuel line 38 to an externally positioned oil reservoir. A gear pump 36conveys the oil from the reservoir by way of lines 33 and 37 to thedaily tank 4, with lines 37 and 33 connected to each other by way of areadily severable connector fitting. For this purpose, line 37 has aflange at its end provided with a soft rubber packing 39 on whichpacking a counter-flange 40 at the end of line 38 presses. Thisseverable connection is positioned above the maximum level of oilpossible in the daily tank so that when it is severed no oil can flowtherefrom. The withdrawal and insertion of the burner assembly in thisembodiment are the same as above described for the FIGURE 1 embodiment.The lever to be actuated in the withdrawal and reinsertion of the burneraggregate of this embodiment is likewise so arranged that the oven doorcannot be closed if the burnor is not in operative condition. Thus,operation of the oven as long as the cylindrical wall of the sealbetween the burner and the oven per se is open, is totally impossible.In the case of assemblies which are not connected to oil reservoirs byway of an oil conveying pump and into which oil must periodically berefilled, such refilling can be substantially simplified by pulling theburner assembly out to a greater or lesser extent, as may be required.Thus, as above stated, the embodiment of FIGURE 1 need be pulled outonly enough to permit removal of cover 4a, while if the embodiment ofFIG- URE 2 would have a cover over packing flange 39 and would then haveto be pulled out that far to remove such cover. In so doing it willreadily be possible to fill the tank without permitting even traces ofoil to overflow, which is important because even a single drop of oil ona wooden floor, for example, will for days generate an unpleasant smellof oil.

Cleaning such an oven according to the invention may be as follows: Thechimney sweep first cleans the oven body and the flame chamber of sootand dust, both of which are initially swept into the pot burner. Oncompletion of such sweeping, the pot burner by actuation of the handlever, and without severing other connections, is moved from the ovenbody and the entire burner assembly withdrawn from the body, where alldirt and foreign matter is now readily removed from the pot burner. Evenmore hygienically and in cleaner fashion, this work can be done asfollows: The chimney sweep first withdraws the burner assembly from theoven body,

and then introduces a paper bag 41 into the pot burner,'-

after which he pushes the assembly back into its operative positionwithin the body and cleans the upper region of the oven. Dust and finelydivided soot, which occur only in this region, fall down into the bag.By again withdrawing the burner assembly from the oven, such dirt, whichis mainly responsible for the unwanted soiling of living quarters, maybe completely removed without further manipulation than removing thebag. Only thereafter are the coarser grained impurities removed from thepot burner.

If a cleaning or repair of the pot burner of such construction were tobe undertaken in the usual prior manner, namely, by disconnecting allthe connections between the pot burner and the other parts of the burnerassembly, appropriate threaded connectors, severable for such purpose,would have to be provided. This must be avoided in view of the pooraccessibility of the burner and the danger that in the course thereofthe fan 26 or the motor 27 might be damaged. Furthermore, repair of thebucket conveyor mechanism would be extremely difficult in the priorforms of construction due to its poor accessibility.

In dismantling ovens due to defects in the burner assembly of theinstant invention, the procedure is as follows: The oven consists ofthree units readily severable from each other, namely, the oven body perse, the burner assembly, and the electrical controls includingthermostats, etc. An interchangeable replacement unit for each theburner assembly and the control elements is brought by the Servicemanwhen making a service call. As a first step, by a simple severance oftwo plug connections, the control elements are removed from the oven andreplaced by the spare control elements unit. If the oven now operates,the repair has been completed. If it should not now operate, theoriginal control elements unit is again replaced, and now the entireburner assembly replaced by the spare burner assembly. In that there canhardly be a defect in the oven body per se, the oven is thereby restoredto operativeness and the repair is finished. The unit found defective onsuch procedure can be forwarded to an appropriately equipped repairshop, where eventually it is restored to operativeness by trainedexperts and can be used as a replacement unit for another oven.

What I claim is:

1. A fully automatic oil oven having vertical and horizontal wallsforming a hollow body, a flame chamber spatially fixed within the bodyand having a centrally apertured bottom, a door in the lower region of avertical wall of the body, a unitary assembly comprising a pottypemixing chamber open at its top, electrical ignition means positioned inthe bottom interior region of the mixing chamber, a closed fuel oiltank, a fuel oil passageway from the tank to the interior of the mixingchamber, spring means for supporting the mixing chamber on the tank andfor yieldably sealing the upper end of the mixing chamber to the bottomof the flame chamber about the central aperture thereof, an electricalconductor, a severable connector having a first and a second element ofwhich the first element is supported on the tank and is connected to theignition means by the conductor, the second element of the connectorbeing on the body in registering position with the first element forconnection to a source of electrical potential, means on the unitaryassembly for lowering and raising the unitary assembly and normallymaintaining the mixing chamber sealed to the flame chamber and the twoelements of the connector in engagement when the unitary assembly is inits fully inserted and oven operative position within the body, saidmeans being manually operable in one direction to lower the unitaryassemblywithin the body and to simultaneously unseal the mixing chamberfrom the flame chamber and to disconnect the two elements of theconnector from each other and in the other direction to raise theunitary assembly and to simultaneously seal the mixing chamber to theflame chamber and to connect the two elements of the connector to eachother, and means on the unitary assembly facilitating movement of theunitary assembly in lowered position longitudinally of itself.

2. The oil oven according to claim 1 in which the means for lowering andraising the unitary assembly is an elongated lever pivoted adjacent tothe bottom of the tank and having a longer upper and a shorter lowerarm, the free end of its lower and shorter arm being provided with aroller engaging the horizontal wall of the walls forming the oven bodyconstituting the bottom of the oven body, the forward end of the unitaryassembly when fully inserted into the oven body being at a distance fromthe front vertical wall of the walls forming the oven body, the lever onbeing deflected forwardly with its upper and longer arm toward thehorizontal lowering at least the front portion of the assemblysufficiently to disengage the mixing chamber from the bottom of theflame chamber, and the lever longer arm being of a length greater thansaid distance between the assembly and the front vertical wall of theoven.

3. The oil oven according to claim 2 in which the bottom of the tank isinclined downwardly from the front to the rear of the tank and the meansfacilitating longitudinal movement of the unitary assembly in loweredposition comprises a pair of rollers journalled at the end region of thetank the more remote from the front vertical oven wall.

4. The oil oven according to claim 2 in which the means facilitatingmoving the unitary assembly longitudinally comprises a pair of rollerson a transverse axle on the bottom of the tank at its region remote fromthe region at which the elongated lever is pivoted.

5. The oil oven according to claim 4 in which when the unitary assemblyis in the operative position within the oven body the bottom of the tankinclines downwardly from its end adjacent to the oven door to its endremote from the door and the elongated lever is pivoted at the tankregion the more adjacent to the oven door so that on the forwarddeflection of the lever the tank is pivoted about the transverse axle ofthe pair of rollers.

6. The oil oven according to claim 1 in which the spring meanssupporting the mixing chamber comprises a cylinder supported on thetank, an internal annular flange integral with the upper end of thecylinder, a piston ing an enlarged head within the cylinder, and aspring biasing the piston head upwardly toward engagement with theflange, the position of the seal between the mixing and flame chambersabove the piston head preventing the engagement when the unitaryassembly is in the operating,

position within the body while allowing such engagement on downwardmovement of the unitary assembly, the continued downward movement aftersuch engagement breakingsaid seal, on operation of the unitary assemblylowering and raising means in said one direction.

7. A fully automatic oil oven comprising vertical and horizontal wallsforming a hollow oven body, a flame chamber having a centrally aperturedbottom, an annular groove in the flame chamber bottom concentric withthe central aperture therethrough, an oven door in the vertical wall ofthe oven body constituting the front of the oven body, a stop on theinternal face of the vertical wall of the oven body constituting therear wall of the oven body and opposite the door, an electrical socketfor connection to a source of electrical energy supported in said rearvertical wall, a unitary assembly for complete insertion into theinterior of the oven body and comprising a pot having a cylindricalwall, an electrical ignition plug centrally disposed at the bottom ofthe pot the cylindrical wall of the pot defining a plurality of airintake apertures, a cylindrical casing closed at its bottom and of adiameter greater than that of the cylindrical wall of the pot disposedabout the pot and taperingly joined at its top to a region close to thetop of the cylindrical wall, the bottom of the cylindrical casing beingspaced from the bottom of the pot, a fan in the region defined betweenthe bottom of the pot and the bottom of the cylindrical casing, anelectric motor for driving the fan, an enclosed fuel tank positionedwithin the oven body between said front and rear vertical walls andhaving a bottom inclined downwardly from its end adjacent to but spacedfrom the oven door to the end remote therefrom, means for supplying oilfrom the tank to the pot, an electrical distributor supported on anupper exterior portion of the tank, electrical connections from thedistributor to the ignition plug and motor respectively, an electricalconnector plug connected to the distributor and supported on theexterior of the wall of the tank remote from the oven door, spring meanssupporting the assembly on the tank top, the spring means including atleast one cylinder supported on the top wall of the tank and having aninternal flange at its top defining a central aperture, a pistonextending through the central aperture of the flange and engaging thebottom of the cylindrical casing, the piston having a shoulder at itslower end region within the cylinder, which shoulder at maximumelevation of the piston engages the internal flange, and a spring withinthe cylinder braced between the top wall of thetank and the pistonshoulder to bias the piston upwardly, first roller means attached to thetank bottom at a region thereof remote from the door and engaging thebottom horizontal wall of the oven body, a lever pivoted to the tank endadjacent the oven door at a region adjacent to the tank bottom, thelever having a long arm upwardly and a short arm downwardly of theregion at which it is pivoted, second roller means at the free end ofthe short arm, the second roller means engaging the bottom horizontalwall of the oven body so that when the lever is in a normal verticalposition the spring presses the upper end of the cylindrical Walltightly into the annular groove in the flame chamber bottom and thepiston shoulder is below and spaced from the internal flange of thecylinder and when the lever is moved forwardly away from the tank towardthe horizontal the lever end of the tank is lowered sufiiciently aboutthe first roller means as a pivot to permit the spring to force thepiston upwardly to engage the internal flange of the cylinder preventingfurther upward movement of the cylindrical wall, the downward movementof the front region of the tank caushaving the top of the cylindricalwall now to leave the groove, and the connector plug to separate fromthe socket, and permitting withdrawal of at least the front end regionof the unitary assembly through the oven door, while on reinsertion intothe oven body of the withdrawn unitary assembly the remote end of thetank strikes the stop and the subsequent restoration of the lever to thevertical position reconnects the connector plug and socket and restoresthe upper end of the cylindrical wall into the annular groove.

8. The fully automatic oil oven according to claim 7 in which the longarm of the pivoted lever is of such greater length than the distancebetween the adjacent end of the tank and the oven door as to permitclosure of the oven door only when the burner assembly is in itselevated position sealing the upper end of the cylindrical wall in theannular groove.

References Cited in the file of this patent UNITED STATES PATENTS

